RT-11 with Basic-11

I have now managed to get a boot disk with RT-11 and BASIC-11 on it (thanks Mark for making *another* boot disk on your PC).  So now I can boot my PDP and write programs on it.  Progress indeed.  Here is something I captured running on my actual PDP-11/53:

...as you can also see, I have also been busy experimenting with the best colours for my terminal emulator.  Today I am mostly programming with grey text on a blue background.  Getting this to work involved taking two 400k RX50 disk images and creating a single 1.2Mb RX33 image.  So I effectively merged the contents of the RT-11XM boot disk and the "Languages Master" disk into a single boot disk.  Works a treat.  This seems to boot much faster now, so I suppose the RX33 drive is much faster at reading 1.2Mb 5.25" floppy disks.

Simple Test Code Generator

I have been working on a C# console application that will output a test application which can be sent to a PDP-11 and executed. Here is a clip of it in action on a simulated PDP-11:

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This example shows the RT-11 'DEPOSIT' command in action, it allows memory locations to be set with a specific value from the command line.  I use that to enter the program and then the 'START' command to start running the code.

Das boot

So the next step with my PDP-11 was to try and boot an OS.  A friend of mine (the kind of bloke who keeps old machines with 5.25" floppy drives) was kind enough to volunteer and make a boot disk.  We used the excellent PUTR utility to make the disk on a PC.  The disk image came from here, we used the RT-11 boot disk.  I will post the PUTR instructions another time.  The first disk we made attempted to boot up, there was a lot of disk activity... but after a few minutes I got the message: "?BOOT-U-I/O error".  We wondered if this was just a bad disk.  Fortunately, we made another disk and tried again...  This time it booted straight into RT-11.  This was the result:

RT11 screenshot

How cool is that?  Some sort of celebration must be in order, consumption of beer seems appropriate for that.